Standard, against which all others of the same category are
measured. Usage: silly. The notion is that one of whatever it is has
actually been cast in platinum-iridium alloy and placed in the vault beside
the Standard Kilogram at the International Bureau of Weights and Measures
near Paris. (From 1889 to 1960, the meter was defined to be the distance
between two scratches in a platinum-iridium bar kept in that same vault
— this replaced an earlier definition as
10-7 times the distance
between the North Pole and the Equator along a meridian through Paris;
unfortunately, this had been based on an inexact value of the circumference
of the Earth. From 1960 to 1984 it was defined to be 1650763.73
wavelengths of the orange-red line of krypton-86 propagating in a vacuum.
It is now defined as the length of the path traveled by light in a vacuum
in the time interval of 1/299,792,458 of a second. The kilogram is now the
only unit of measure officially defined in terms of a unique artifact. But
this will have to change; in 2003 it was revealed that the reference
kilogram has been shedding mass over time, and is down by 50 micrograms.)
“This garbage-collection algorithm has been tested against the
platinum-iridium cons cell in Paris.” Compare
golden.